Bobbin carrier mount for sewing machines&#39; rotary loopers



Jan. 8, 1963 1.. VIGORELLI BOBBIN CARRIER MOUNT FOR SEWING MACHINES ROTARY LOOPERS Filed Oct. 20,

United States Patent 3,072,084 BOBBIN CARRIER MOUNT FOR SEWING MA- CHINES RGTARY LUOPERS Luigi Vigorelli, 1 Viaie Lungo Ticino Visconti, Pavia, Italy Filed Oct. 20, 1959, Ser. No. 847,617 Claims priority, application Italy Oct. 21, 1958 4 Claims. (Cl. 112-180) This invention relates to lower stitch forming mechanisms in sewing machines and, more particularly, it is related to a new and improved movable bobbin carrier mount for stitch forming or looper mechanisms of the rotary type, including a rotary looper member rotatably supported and driven about an horizontal aXis and a bobbin carrier mount hingedly connected to the machines base frame structure, adapted to be positioned for operation in juxtaposed and co-axial relationship with said looper and to be set at an angle in respect to said axis for opening of the assembly namely for taking the said bobbin out, say for refilling or substituting the same.

It is known to those skilled in the art to which this invention appertains that such rotary loopers, while well accepted in view of their satisfying operation in stitch forming, are subject to several objections in view of a somewhat difiicult and troublesome handling thereof during the above suggested bobbin taking out and substitution. In the rotary looper bobbin carriers constructed and arranged in the sewing machine base according to current practice, the said bobbin and bobbin carrier are difficult to reach, owing to the small amplitude of the space left at disposal of the operator for taking hold of the carrier for removal thereof and re-fitting the same in proper position. In addition, during the return motion of the mount towards stitch forming mechanism closed or operative position, the bobbin carrier is subject to undesirable displacement from its correct position, and the service of the sewing machine may be therefore prejudiced.

Further, in the conventional constructions and arrangements of stitch forming mechanisms in the base portions of currently produced sewing machines, the said mechanism is positioned well deeply below the machines cloth table and it may be reached by the operators fingers through a small sized opening actuated upon displacement of an hinged or slidable small sized plate in said cloth table. Proper setting of the bobbin carrier on the hingedly supported mount is impractical and hazardous.

It is therefore an object if this invention to provide an improved movable mount assembly for rotary stitch forming mechanisms of the type considered, wherein the mount is movably supported in the machine base structure for operator-actuated displacement from the looper operative close position to an open condition at which the said bobbin carrier is readily positioned for getting hold thereof.

Another object of this invention is to provide a new and improved rotary loopers bobbin carriers displaceable mounts including bobbin and bobbin loopers holding devices designed for safely taking hold of such elements during the displacement of mount, whereby the said bobbins and bobbin carriers may be safely displaced into their proper position in respect to the related rotary looper, and then for leaving the said bobbin carrier fully free within the stitch forming mechanism in its operative condition, as required for free passage of thread thercabont in the looping and stitch forming operation.

In addition, under normal circumstance, it is rather difficult to obtain the displacement or shifting, and the locking and unlocking of the carrier mount, deeply positioned under the cloth table, by acting through the said small sized opening in the said table, but in this invention, according to a further object thereof, arrangement is made whereby the said displaceable carrier looper is drivingly connected to said opening closure forming slidable plate for having the various carrier mount locking and unlocking and displacement steps directly performed by operating the said slidable plate only namely by sliding on and off same.

These and other objects and advantages of the invention are in part obvious and in part will be made apparent as this description proceeds, and the features which are believed to be new and characteristic of the invention are in particular set forth in the appended claims. The invention itself, however, both as to its construction and to its mode of operation, will be best understood from the following detailed description of a preferred form of embodiment thereof, when taken in conjunction with the accompanying drawing, forming an essential component of this disclosure, and wherein the structural and operative elements appertaining to current knowledge are illustrated and drawn by and with light drafted lines, for best visualization of the features of interest for the invention.

In the drawing:

FIGURE 1 is a side vertical elevational view of the assembly constructed according to the invention, with the stitch forming mechanism in its working condition;

FIGURE 2 is a vertical longitudinal sectional view of same, upon the first preparatory step of looper opening operation; and

FIGURES 3 and 4 are side elevational views corresponding to the view of FIG. 1, and wherein the mount is shown as upon completion of the opening and respectively of the mount displacement steps.

In the figures, the sewing machines frame is shown in cross-sectional view, and like reference numerals refer to like parts and members. Referring now to the drawing:

The stitch forming mechanism of the sewing machine includes a rotary looper generally indicated at 10, a bobbin carrier generally indicated at 11 and a bobbin carrier mount generally indicated at 12.

Such components are of ordinary construction and are not deemed necessary here further to be described.

In addition, according to current construction, the said machine base structure includes a cloth table forming plate 17 and a slidable plate 15 in flush with said cloth tabl and adapted to be slidably displaced in direction B for providing an opening 16 (FIG. 4) in the said cloth table. The size and the location of said opening are pretty small and respectively pretty out-set in respect to the stitch forming mechanism arranged beneath said plate 17, such undesirable features being an unavoidable consequence of standard sizing of the cloth tables in commercial sewing machines and respectively of the location of feed-dog means (not shown) just above the said mechanism.

According to an object of this invention, the said slidable plate 15 is drivingly connected to the bobbin carrier mount and to the mount carrying elements described below. Such connection consists of an L-shaped brace member 18 secured to said plate 15 and downwardly extended therebelow. Two small links 19 symmetrically located at both sides of the mount (and one of which only is shown in the elevational side views of the device) are pivotally connected to said brace member 18 and articulately connected to the conventionally constructed base plate 23 of the mount 13 by means of pivot-forming pins 20 secured to side portions of said plate 23. Such pins are slidably engaged into longitudinally elongated slots 25, the elongation of which is such to allow a certain rightward motion of slidable plate 15 in opening direction B, before causing a motion in the bobbin carrier mount.

The said pins 20 are further slidably engaged into guiding slots provided into side plates secured to a portion 13 of the machines base frame structure, the said guiding slots including a left arc-shaped portion 21 having its center in the pivotal axis at 14 and a right upwardly inclined straight portion 22. In addition, the said mount plate 23 is slidably supported on a parallel and adjacent plate 24 hingedly connected at 14 to the said portion 13 of the machines base frame structure, and therefore adapted for rotation in direction A (FIG. 3) about the axis of said hinge connection at 14, together with said mount 12.

In addition, the said mount plate 23 pivotally supports a small two-armed lever 26 which, as it may be particularly seen in FIG. 2, includes a lower end portion 27 in abutting relationship with and adjacently and oppositely located lower end portion 28 of said brace 18 and an upper end portion 29 engaged into a slot in a bobbin carrier securing pin 30 co-axial to the said carrier and slidably supported into a tubular guide means made integral with the bobbin carrier mount structure. A spring 31 (FIG. 2) leftwardly urges the said pin through an hole in said mount plate 23 within the central hole with which the standard manufactured bobbin carrier for rotary loopers of the type considered are provided.

The above described components are arranged and set as the device is in its operative condition of FIG. 1 so that the said lower portion 28 of brace 18 'keeps'the end 27 of lever 26 pressed and therefore the said securing pin 30 urged outside the bobbin carrier hole, for leaving the said carrier free in the interior of the closed and operatively conditioned stitch forming mechanism.

The relative movements and the corresponding effects of the components of the above described device maybe readily understood upon comparative consideration of the various figures of the accompanying drawing. By manually displacing the'slidable plate when the stitch forming device is at its regular operative condition of FIG. 1, the first part of such displacement, until the position of parts illustrated in FIG. 2, corresponds to the elongation of slots 25 wherealong the pins may slide. During such first partial motion of plate 15, the corresponding rightward motion of lower end portion 28 of brace 18 causes the two-armed lever 26 to pivotally rotate in direction D (FIG. 2') 'under the action of spring 31, and the 'pin 30 to leftward move in direction E until penetration of its left end portion into the bobbin carrier.

Therefore the above first step of operation of the de vice of the invention actuates the securing of the bobbin carrier on the mount, prior to opening of the stitch forming mechanism and prior to any motion of the very components of such mechanism.

Upon completion of such first partial motion, the pin 20 engages the left end of the elongated slot and, therefore, any further rightward motion of brace 8 would cause the motion of bobbin carrier mount. The furtherpartial motion causes the parts to relatively move from the position of FIG. 2 to the position of FIG. 3, namely it causes the mount 12,together with the plate 23 and the bobbin carrier 11, to pivot in direction A about the hinge axis at 1 While the pin 26 guidedly slides along the arc-shaped portion 21 of guide slots.

Such second partial movement of parts corresponds to the regular opening motion of conventionally constructed rotary stitch forming mechanisms. Upon completion of such second partial movement, the said mount cannot further rotate in direction A about pivots at 14 because the pins 24) have come in abutting relationship with the right end of arc-shaped portions 21 of guide slots, and, there- 'fore, any further rightward motion of said pins and therefore of mount 12 will forcedly follow the direction definedby the straight positions 22 of same guide slots.

rier 11 in a position very weil adapted for easily taking hold thereof by the operator.

The inverted cycle of operations and steps will occur as the said sliding plate 15 is returned, in direction opposite to B, from its fully open position of PEG. 4 to its fully closed position of FIG. 1. As a first step of closing operation, the mount carrier 12 is caused to downwardly slide in position of FIG. 3 wherein it is conditioned for back pivoting in its closed position of PEG. 2, occurring in the second step of closing movements.

The last closing step causes the securing pin 30 to rightwandly return in its retreated position, leaving the bobbin carrier, already well closed in the stitch forming mechanism, free inside the said mechanism for passage and looping of thread thereabout during the sewing procedure.

It will be further readily understood that the invention includes means, namely consisting of the securing pin 30, which ensures the correct location of the bobbin carrier in regular co-axial relationship with the carrier mount until the components of the device have attained their fully closed condition. Such feature will prevent any possible displacement of relative position of bobbin carrier and of mount during all and each movements thereof, even if briskly performed.

in the practical use of the invention, the various described steps and movements will not be obviously distinguished by operator, who will simply moving back and forth the slidable plate 15 for having the bobbin carrier extracted from the iooper and brought in an easily accessible location and respectively for restoring the stitch forming mechanism in its operative condition, upon seating of bobbin carrier on its mount, in proper co-axial condition, as guidedly facilitated by the location of bobbin carrier on and about the pin 28 slightly Corning forth on the inner surface of mount.

It is moreover believed to be evident that the present invention includes a plurality of advantageous features, and it will be understood that each of the new features described and any combination thereof may also find useful application in other constructions of rotary stitch forming mechanisms and devices dithering from the ones described.

Without further analysis, the foregoing will so fully reveal the gist of this invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of this invention and, therefore, such adaptations should and are intended to be comprehended wit .in the spirit and meaning of equivalent of the invention, as defined in and by the appended claims.

Having thus described the invention and the mode of carrying out thereof, what is claimed as new and desired to have protected by Letters Patent is:

1. In a sewing machine, in combination, a machine bed having an opening; a rotary loop-taker fixedly mounted on said machine bed; a bobbin case adapted to hold a bobbin; a support fixed on said machine bed and including guide means having parallel guide slots, each slot having a circular portion and a straight portion extending at one angle to said circular portion and toward said opening; a mounting plate pivotally mounted on said support; a mount; means supporting said mount on said mounting plate for pivotal movement with the same and for a sliding movement on the same so that said mount supports said bobbin case for movement therewith between a sewing position located in said loop-taker and a raised bobbinchanging position located outside of said loop-taker in the region of said opening, said mount having a pair of guide members guided in said slots of said guide means; and manually movable means mounted on said machine bed and operatively connected to said mount for first pivoting said mounting plate with said mount about said support, under the guidance of said guide means, and for then shifting said mount along said mounting plate under the guidance of said guide means so that said bobbin case moves with said mount from said sewing position to said bobbin-changing position.

2. in a sewing machine, in combination, a machine bed having an opening, a loop-taker mounted on said machine bed; a bobbin case adapted to hold a bobbin; a mounting member pivotally mounted on said machine bed; a mount supporting said bobbin case; means for supporting said mount on said mounting member for pivotal movement with the same and for a sliding movement on the same; guide means fixed on said machine bed and having a guide track for guiding a portion of said mount so that said mount is movable with said bobbin case between a sewing position in which said bobbin case is located in said loop-taker and a raised bobbinchanging position in which said bobbin is located outside of said loop-taker and in the region of said opening of said machine bed; a manually operated closure plate movable between a closed position closing said opening in said machine bed and an open position; and linkage means connecting said closure plate with said mount so that the same moves along said guide track during movement of said closure plate, said linkage means and guide track being arranged and constructed in such a manner that said bobbin case is in said sewing position when said closure plate is closed, and is in said bobbin-changing position when said closure plate is open.

3. In a sewing machine, in combination, a machine bed having an opening, a loop-taker mounted on said machine bed; a bobbin case adapted to hold a bobbin; a. mounting member pivotally mounted on said machine bed; a mount supporting said bobbin case; means for supporting said mount on said mounting member for pivotal movement with the same and for a sliding movement on the same; guide means fixed on said machine bed and having a guidetrack for guiding a portion of said mount so that said mount is movable with said bob- 'bin case between a sewing position in which said bobbin case is located in said loop-taker and a raised bobbinchanging position in which said bobbin is located outside of said loop-taker and in the region of said opening of said machine bed; a manually operated closure plate movable between a closed position closing said opening in said machine bed and an open position; and linkage means connecting said closure plate with said mount so that the same moves along said guide track during movement of said closure plate, said linkage means and guide track being arranged and constructed in such a manner that said bobbin case is in said sewing position when said closure plate is closed, and is in said bobbin-changing position when said closure plate is open, said linkage means including a bracket secured to said closure plate, a ling articulated to said bracket and having a slot, and a pin secured to said mount and being located in said slot so that said bracket moves relative to said mount during the opening of the closure plate before moving said mount along said guide track; a holding member mounted on said mount for movement between a holding position holding said bobbin case, and a normal position releasing said bobbin case for cooperation with said looptaker; spring means urging said holding member to said holding position, said holding member including a part engaged by said bracket means in said closed position of said closure plate in such a manner that said holding member is held in said normal position releasing said bobbin case, said bracket member releasing said part during the first portion of the movement of the closure plate out of said closed position while said pin moves in said slot of said link so that said holding member moves to said holding position under the action of said spring before said mount moves along said guide track with said bobbin case.

4. In a sewing machine, in combination, a machine bed having an opening; a loop-taker mounted on said machine bed; a bobbin case adapted to hold a bobbin; 3. guide means fixed on said machine bed and including a guide track having a lower portion and a higher portion and extending between said loop-taker and said opening; means supporting said bobbin case for movement along said guide track for movement between a lower position in which a bobbin located in said bobbin case is in a sewing position cooperating with said loop-taker and a higher position in which said bobbin case is located in said opening and easily accessible; a closure plate for said opening in said machine bed movable between a closing position closing said opening and an open position; and linkage means connecting said closure plate with said bobbin case so that manual movement of said closure plate from said closing position to said open position efiects movement of said bobbin case along said guide track from said lower position to said higher position, and vice versa.

References Cited in the file of this patent UNITED STATES PATENTS 521,372 Holroyd et a1. June 12, 1894 1,941,083 Goosman Dec. 26, 1933 2,507,470 Hirsch May 9, 1950 2,671,420 Backlin Mar. 9, 1954 FOREIGN PATENTS 697,979 Germany Oct. 29, 1940 

1. IN A SEWING MACHINE, IN COMBINATION, A MACHINE BED HAVING AN OPENING; A ROTARY LOOP-TAKER FIXEDLY MOUNTED ON SAID MACHINE BED; A BOBBIN CASE ADAPTED TO HOLD A BOBBIN; A SUPPORT FIXED ON SAID MACHINE BED AND INCLUDING GUIDE MEANS HAVING PARALLEL GUIDE SLOTS, EACH SLOT HAVING A CIRCULAR PORTION AND A STRAIGHT PORTION EXTENDING AT ONE ANGLE TO SAID CIRCULAR PORTION AND TOWARD SAID OPENING; A MOUNTING PLATE PIVOTALLY MOUNTED ON SAID SUPPORT; A MOUNT; MEANS SUPPORTING SAID MOUNT ON SAID MOUNTING PLATE FOR PIVOTAL MOVEMENT WITH THE SAME AND FOR A SLIDING MOVEMENT ON THE SAME SO THAT SAID MOUNT SUPPORTS SAID BOBBIN CASE FOR MOVEMENT THEREWITH BETWEEN A SEWING POSITION LOCATED IN SAID LOOP-TAKER AND A RAISED BOBBIN- 